The present invention relates to electronic data processing in general, and particularly to declaring application data.
In the model view controller (MVC) design pattern used for developing application programs, the model represents the core of such an application program. The model can have multiple views, where each view displays information about the model to a user. A controller of the model receives events, for example, raised by a user interacting with a view to manipulate the model. The model can have multiple controllers and a controller can relate to multiple views. The model and the controller typically include application code. When changes occur in the model, the model updates all of its views. Data binding is used for data transport between the view and its model or controller. For example, a table view can be defined to display data of a corresponding table that is stored in the model or controller. The table is used as the data source for the table view (data binding). For example, the table view can be replaced by a further view, such as a linked list, that binds against the same table. In this case, the further view displays the table data without changing anything in the controller or the model.
When building a software application, predefined relationships can exist between various data elements used by the application. Predefined relationships can be defined in a variety of ways; for example, the relationships can be defined through dependencies in a relational database. However, for some data, predefined relationships do not exist, for example, when no relationship is defined in a database or when it is data that refers to the model on the one hand and to the view on the other hand. Therefore, usually a major portion of the application's code is devoted to defining the corresponding relationships and to enabling the data transport, for example, from the model to the view.
Further, at a given point in time an application has a specific state that reflects the current status of the interaction of the user with the application (e.g., on which view is the cursor of the application and which row of a specific table in the view has been selected by the user). Typically, an application developer has to write application coding to memorize and administrate the state (e.g., by using state variables).
Further, when the user of a client-server system interacts with the client, typically the client sends a request to the server to rebuild a current page and the server sends the rebuilt page to the client. This may cause an unpleasant effect for the user in the form of a flickering picture on a display device of the client. Some client-server systems support mechanisms to rebuild only mandatory components of the page and send only the corresponding delta information to the client to reduce flickering. However, to determine the delta information, application-specific coding may have to be developed on both sides, the client and the server.